The present invention relates to fasteners typically referred to as flag nuts.
In order to secure two or more workpieces together, fasteners such as bolts or screws may be inserted through aligned apertures in the workpieces such that a head of the bolt or screw is positioned against the outer surface of one of the workpieces and the elongated threaded shaft that extends therefrom, extends beyond the outer surface of the other workpiece. In order to ensure tight securement of the bolt or screw to the workpieces, a nut having a threaded aperture therethrough is generally positioned around the shaft of the bolt or screw until it is positioned in tight engagement against the outer surface of the other workpiece.
In many applications, though, the nut needs to be placed in a location where there is limited access for a drive tool or even a hand wrench to tighten the nut. An earlier solution to this problem was the creation of a flag nut. The flag was a small piece of material to which the nut was attached. The flag protruded perpendicularly from the axis of the nut and, upon tightening of the nut, as the nut rotated, the flag caught on any nearby structure, for instance, a frame, such that the flag acted as a wrench during the tightening process.
Generally, flag nuts are two-piece designs. One known two-piece design has a spring steel flag crimped over a hex flange nut while another known two-piece design has the nut staked, welded or pierced onto or into the flag. These two known two-piece designs present certain problems.
With regard to the spring steel flag crimped to the nut, the spring steel flags, while having the appropriate level of stiffness and hardness, often also commonly suffer from brittle failures, including stress fractures and stress corrosion failures. This is because after stamping the shape of the flag, the part must be heat treated and, thus, the flag becomes highly stressed such that the brittle failures of the spring steel flags may occur. With regard to the staking, welding or piercing of the nut to the flag, there is always a question of the integrity of the stake, weld or pierce. Both designs are also complex, weighty, add to the manufacturing costs, and have the problem of having parts coming loose.
Flag nuts of the prior art also may have sharp edges which may come into contact with a structural member during installation. If the edge of the flag nut is sharp, the edge of the flag nut may hang up on the structural member during attachment such that the nut will not seat properly.
Thus, there is a need for a flag nut which overcomes disadvantages presented by two-piece flag nut designs.
A primary object of an embodiment of the present invention is to provide a one-piece flag nut which has a flag portion which protrudes perpendicularly from the axis of a nut portion and where, upon tightening, as the flag nut rotates, the flag portion catches on any nearby structure and acts as a wrench during the tightening process.
An object of an embodiment of the present invention is to provide a one-piece flag nut that is not heat treated and, therefore, is not as likely to be susceptible to cracking or to brittle failures, including stress fractures and stress corrosion failures.
Another object of an embodiment of the present invention is to provide a one-piece flag nut that has ribs formed on the flag portion thereof to stiffen the one-piece flag nut in order to reduce buckling and bending of the flag portion during installation.
Another object of an embodiment of the present invention is to provide a one-piece flag nut that has rolled edges to prevent the flag portion of the one-piece flag nut from being snagged or hung up during nut rundown on the bolt.
Another object of an embodiment of the present invention is to provide a one-piece flag nut that has outer edges which maintain uniform material thickness throughout the installation because of being formed by an extrusion process, thus maintaining uniform strength of the one-piece flag nut.
Still another object of an embodiment of the present invention is to provide a one-piece flag nut which has reduced complexity in comparison to flag nuts of the prior art.
Yet another object of an embodiment of the present invention is to provide a one-piece flag nut which has a reduced weight in comparison to flag nuts of the prior art.
Another object of an embodiment of the present invention is to provide a one-piece flag nut which requires a lower manufacturing cost in comparison to flag nuts of the prior art.
Still another object of an embodiment of the present invention is to provide a one-piece flag nut which does not have separate parts such that loose parts can come loose during installation.
Another object of an embodiment of the present invention is to provide a one-piece flag nut which will not have questions about the integrity of a weld, stake or pierce.
Briefly, and in accordance with the foregoing, an embodiment of the present invention provides a one-piece flag nut having a flag portion protruding perpendicularly to the axis of a nut portion thereof such that during installation, as the flag nut rotates, the flag portion catches on any nearby structure and acts as a wrench during the installation process. The one-piece flag nut is formed by an extrusion process. The one-piece flag nut is further formed to have ribs provided on the flag portion thereof which provide added strength to the flag nut. The outer edges of the flag portion are also rolled to prevent the flag portion from being hung up on the structure during the installation process, thus preventing the flag nut from being properly seated.